<p>There are two types of respiration that you need to know about - aerobic and anaerobic respiration. The main difference between the two types of respiration depend on whether oxygen is available or not. Aerobic respiration occurs when oxygen is present, but anaerobic respiration occurs when oxygen is not present (to help you remember this, remember that anaerobic respiration occurs during hard exercise, when you are using a lot of oxygen). Aerobic respiration converts glucose to carbon dioxide and water, while anaerobic respiration converts glucose to lactic acid (which builds up during hard exercise). A lot more energy is produced by aerobic respiration compared to anaerobic respiration. Reactions for anaerobic mainly occur in the cytology, while aerobic reactions occur in the mitochondria.</p><p>Another explanation would be: Aerobic respiration requires glucose and oxygen, while anaerobic respiration only requires glucose. The glucose is completely broken down in aerobic respiration whereas in anaerobic respiration it is only partially broken down. The end products of aerobic respiration are carbon dioxide and water. In anaerobic respiration the end products differ depending on the type of cell. In animal cells the end product is lactic acid whereas in plant cells and yeast the end products are carbon dioxide and ethanol. Aerobic respiration releases 19 times more energy than anaerobic respiration. </p>